Sea Level Rise
Climate is having a massive impact on the oceans. Warmer air with increasing concentration of carbon dioxide is causing two main problems: sea level rise and ocean acidification. For many people—especially those who live near coasts—their primary concern is in the indisputable fact that sea levels are rising around the world. This is being caused by the warming effect of the atmosphere of ocean waters, which warming causes the total volume of the sea to expand. Additionally, warmer temperatures around the globe are causing a net loss of land-based glaciers, allow more of this previously stored water to flow into the ocean. Sea level rise is a big problem for cities located by coastline and homeowners with beachfront property. We are providing some resources and references about sea level risk to help you understand your risk. Unfortunately, while sea level rise is important, the impacts on our future well-being is dwarfed by the risks posed to the health of marine ecosystems by the other impact of climate change: ocean acidification.
Global warming has raised global sea level about 8 inches since 1880, and the rate of rise is accelerating. Rising seas dramatically increase the odds of damaging floods from storm surges. A Climate Central analysis finds the odds of “century” or worse floods occurring by 2030 are on track to double or more, over widespread areas of the U.S. These increases threaten an enormous amount of damage. Across the country, nearly 5 million people live in 2.6 million homes at less than 4 feet above high tide — a level lower than the century flood line for most locations analyzed. And compounding this risk, scientists expect roughly 2 to 7 more feet of sea level rise this century — a lot depending upon how much more heat-trapping pollution humanity puts into the sky.
Search Climate Central’s interactive tools to see maps of areas below different amounts of sea level rise and flooding, down to neighborhood scale, matched with area timelines of risk. The tool also provides statistics of population, homes and land affected by city, county and state, plus links to factsheets, data downloads, action plans, embeddable widgets, and more.
Sea-level rise has cost homeowners on the East and Gulf coasts nearly $16 billion in property value as floods and the threat of flooding drive some buyers away, according to a study released yesterday. Analysts at the nonprofit First Street Foundation in Brooklyn studied millions of residential home sales in 17 states from Maine to Alabama and found that coastal property values were rising at a slower rate in flood-prone areas than in areas that did not flood. “The market is already reacting,” First Street Executive Director Matthew Eby said. “There’s no longer a conversation of what sea-level rise will do in 2050 or 2100.”
Acidification, De-oxygenation and Extinctions
Scientists have figured out that approximately 30% of all of mankind’s excess atmospheric CO2 emissions — more than 1.5 trillion tons of CO2 — has been absorbed by the oceans already. The effect of this carbonization is causing the ocean to become less alkaline, i.e. to have a lowering pH and correspondingly greater acidity. This is causing a fundamental change in the chemistry of the ocean from pole to pole, broadly called “ocean acidification.” Ocean acidification is affecting the entire marine environment, causing increasingly dire impacts on marine life and sea food chains.
Since the industrial revolution, the atmospheric concentration of carbon dioxide has increased from 280 to over 400 parts per million due to the burning of fossil fuels such as coal, gas, and oil, along with land use change. The world’s surface ocean is tightly linked with the atmosphere and absorbs huge amounts of carbon dioxide each year. This exchange, in part, helps to regulate the planet’s atmospheric CO2 concentrations — were it not for ocean uptake of CO2, atmospheric CO2 levels would be increasing at an even greater rate than they are now. But, it comes at a cost for the oceans and ocean life; from the smallest, single-celled algae to the largest whales.
Ocean acidification is causing ecosystems and marine biodiversity to change. Rapidly-shifting ocean chemistry has been widely blamed for observed recent damage to coral reef colonies, which negatively impact the marine food chain and fish reproductive processes for the surrounding areas. These changes have the potential to affect both marine life and food security for the entire planet, as most nations get a substantial portion of human food from the sea. Scientists and policy makers are now concerned that our carbon emissions, which are rapidly changing the oceans’ chemistry, will cause a mass extinction within the oceans as a direct result of what we generally think of as “climate change” but whose impacts are substantially broader and far more devastating than many people widely recognize.
While the CO2 that has already been absorbed has helped to moderate the degree of planetary warming we’ve experienced to date, the ocean’s limited capacity to continue absorbing CO2 from human emissions poses considerable climate “tipping point” risks to humans. Once the ocean capacity to absorb more CO2 diminishes, more of the carbon dioxide we emit will remain in the atmosphere, further aggravating global warming and evincing a rapid acceleration of the rate at which the climate changes. When that happens, few species will be equipped to adapt to such unprecedented rates of climate change.
It is widely believed that the economic impact of continued ocean acidification to be substantial, especially with the risk of collapse of fisheries around the world. Reducing and eventually eliminating our CO2 emissions is the only way to minimize long-term, large-scale risks. Reducing the amount of excess carbon dioxide in the oceans through specific activity to draw down and remove the level of excess carbon, will be the only way to begin to restore full health to the ocean.
Click this image to hear Ken Caldeira interviewed by Richard Harris of NPR News.
We invite you to read more of the original scientific literature widely available about the impacts of ocean acidification. Here are some of the studies that we’ve found.
Woods Hole Oceanographic Institution, January 29, 2018
Summary: The rising acidity of the oceans threatens coral reefs by making it harder for corals to build their skeletons. A new study identifies the details of how ocean acidifcation affects coral skeletons, allow scientists to predict more precisely where corals will be more vulnerable.
Science Magazine, January 5, 2018
Summary: As plastic waste pollutes the oceans and fish stocks decline, unseen below the surface another problem grows: deoxygenation. Breitburg et al. review the evidence for the downward trajectory of oxygen levels in increasing areas of the open ocean and coastal waters. Rising nutrient loads coupled with climate change—each resulting from human activities—are changing ocean bio-geochemistry and increasing oxygen consumption. This results in destabilization of sediments and fundamental shifts in the availability of key nutrients. In the short term, some compensatory effects may result in improvements in local fisheries, such as in cases where stocks are squeezed between the surface and elevated oxygen minimum zones. In the longer term, these conditions are unsustainable and may result in ecosystem collapses, which ultimately will cause societal and economic harm.
Florida State University, January 5, 2018
Summary: Accelerating ocean acidifcation could be transforming the fundamental structure of California mussel shells, according to a new report from a Florida State-led team of scientists. For thousands of years, California mussel shells have shared a relatively uniform mineralogical makeup — long, cylindrical calcite crystals ordered in neat vertical rows with crisp, geometric regularity. But in a study published this week in the journal Global Change Biology, researchers suggest that escalating rates of ocean acidification are shaking up that shell mineralogy on its most basic structural levels.
University of Plymouth, January 9, 2017
Summary: Ocean acidification and the extent to which marine species are able to deal with low pH levels in the Earth’s seas, could have a significant influence on shifting the distribution of marine animals in response to climate warming, as reported by ScienceDaily.
Universitat Autònoma de Barcelona, July 12, 2016
Summary: Researchers warn of the negative impacts of rapid ocean warming and ocean acidification on cocolithophores, and consequently in the regulatory processes of atmospheric and ocean concentrations of carbon dioxide, as reported by ScienceDaily.
Expertsvar, January 12, 2016
Summary: Marine bacteria are heavily influenced by the ongoing ocean acidification caused by human emissions of carbon dioxide. “It is well known that the acidification of our oceans causes the degradation of coral reefs and disturbs the production of the calcareous shells of important phytoplankton,” says Jarone Pinhassi, professor in marine microbiology at Linnaeus University in Kalmar, Sweden. “However, it is new that also bacteria are affected negatively by ocean acidification.” (ScienceDaily)
University of Southampton, November 27, 2014
Summary: A study of ancient marine algae has found that climate change affected their growth and skeleton structure, which has potential significance for today’s equivalent microscopic organisms that play an important role in the world’s oceans. Coccolithophores, a type of marine algae, are prolific in the ocean today and have been for millions of years. These single-celled plankton produce calcite skeletons that are preserved in seafloor sediments after death. Although coccolithophores are microscopic, their abundance makes them key contributors to marine ecosystems and the global carbon cycle. The research, published in Nature Communications, examined preserved fossil remains of coccolithophores from a period of climate warming and ocean acidification that occurred around 56 million years ago – the Paleocene Eocene Thermal Maximum (PETM) – and provides a much-needed long-term perspective of coccolithophore response to ocean acidification.
Maria Byrne, Melanie Ho, Eunice Wong, Natalie A. Soars, Paulina Selvakumaraswamy, Hannah Shepard-Brennand, Symon A. Dworjanyn, andrew R. Davis, December 22, 2010. DOI: 10.1098/lrspv.2010.2404
Summary: A study of ancient marine algae has found that climate change affected their growth and skeleton structure, which has potential significance for today’s equivalent microscopic organisms that play an important role in the world’s oceans. Coccolithophores, a type of marine algae, are prolific in the ocean today and have been for millions of years. These single-celled plankton produce calcite skeletons that are preserved in seafloor sediments after death. Although coccolithophores are microscopic, their abundance makes them key contributors to marine ecosystems and the global carbon cycle.
Ocean Acidification: Bringing information on ocean acidification to scientists, policymakers and the public. (This site is a collaboration between the Scientific Committee on Oceanic Research (SCOR), established by the International Council for Science (ICSU) in 1957 and a number of other international ocean research organizations.)
NOAA Ocean Acidification Program: NOAA’s Ocean Acidification Program seeks to better prepare society to respond to changing ocean conditions and resources by expanding understanding of ocean acidification, through interdisciplinary partnerships, nationally and internationally. Ocean acidification is occurring because our ocean is absorbing carbon dioxide from the atmosphere, leading to lower pH and greater acidity. This is causing a fundamental change in the chemistry of the ocean from pole to pole.
National Geographic: Ocean Acidification: Carbon dioxide in the water puts shelled animals at risk, April 27, 2017.
Science Daily: Your source for the latest research news.
Alex Canara, who has shared generously of his hand-outs and admonishments not to focus exclusively on climate change but to recognize both the seriousness and immediacy of the risks of collapse of the marine systems within the oceans.
[Note: Ocean acidification experts: We could use your help. Please consider taking ownership of this page and keeping it updated!]